/*
This file is part of CanFestival, a library implementing CanOpen Stack.

Copyright (C): Edouard TISSERANT and Francis DUPIN

See COPYING file for copyrights details.

This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.

This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
*/

#include <stdio.h>
#include <string.h>
#include <errno.h>
#include <fcntl.h>

#include "canmsg.h"
#include "lincan.h"

#include "can_driver.h"

/*********functions which permit to communicate with the board****************/
UNS8 canReceive_driver(CAN_HANDLE fd0, Message* m)
{
    int res;
    struct canmsg_t canmsg;
    canmsg.flags = 0; /* Ensure standard receive, not required for LinCAN>=0.3.1 */
    do
    {
        res = read(fd0, &canmsg, sizeof(canmsg_t));
        if ((res < 0) && (errno == -EAGAIN))
        {
            res = 0;
        }
    } while (res == 0);
    if (res != sizeof(canmsg_t))   // No new message
    {
        return 1;
    }
    if (canmsg.flags & MSG_EXT)
    {
        /* There is no mark for extended messages in CanFestival */;
    }
    m->cob_id = canmsg.id;
    m->len = canmsg.length;
    if (canmsg.flags & MSG_RTR)
    {
        m->rtr = 1;
    }
    else
    {
        m->rtr = 0;
        memcpy(m->data, canmsg.data, 8);
    }
    return 0;
}

/***************************************************************************/
UNS8 canSend_driver(CAN_HANDLE fd0, Message const* m)
{
    int res;
    struct canmsg_t canmsg;
    canmsg.flags = 0;
    canmsg.id = m->cob_id;
    canmsg.length = m->len;
    if (m->rtr)
    {
        canmsg.flags |= MSG_RTR;
    }
    else
    {
        memcpy(canmsg.data, m->data, 8);
    }
    if (canmsg.id >= 0x800)
    {
        canmsg.flags |= MSG_EXT;
    }
    res = write(fd0, &canmsg, sizeof(canmsg_t));
    if (res != sizeof(canmsg_t))
    {
        return 1;
    }
    return 0;
}

/***************************************************************************/
int TranslateBaudeRate(char* optarg)
{
    if (!strcmp(optarg, "1M"))
    {
        return 1000000;
    }
    if (!strcmp(optarg, "500K"))
    {
        return 500000;
    }
    if (!strcmp(optarg, "250K"))
    {
        return 250000;
    }
    if (!strcmp(optarg, "125K"))
    {
        return 125000;
    }
    if (!strcmp(optarg, "100K"))
    {
        return 100000;
    }
    if (!strcmp(optarg, "50K"))
    {
        return 50000;
    }
    if (!strcmp(optarg, "20K"))
    {
        return 20000;
    }
    if (!strcmp(optarg, "none"))
    {
        return 0;
    }
    return 0x0000;
}

/***************************************************************************/
UNS8 canChangeBaudRate_driver(CAN_HANDLE fd0, char* baud)
{
    struct can_baudparams_t params;
    params.baudrate = TranslateBaudeRate(baud);
    if (params.baudrate == 0)
    {
        return 0;
    }
    params.flags = -1;  // use driver defaults
    params.sjw = -1;    // use driver defaults
    params.sample_pt = -1;  // use driver defaults
    if (ioctl((int)fd0, CONF_BAUDPARAMS, &params) < 0)
    {
        fprintf(stderr, "canOpen_driver (lincan): IOCTL set speed failed\n");
        return 0;
    }
    return 1;
}

/***************************************************************************/
static const char lnx_can_dev_prefix[] = "/dev/can";

CAN_HANDLE canOpen_driver(s_BOARD* board)
{
    int name_len = strlen(board->busname);
    int prefix_len = strlen(lnx_can_dev_prefix);
    char dev_name[prefix_len + name_len + 1];
    struct can_baudparams_t params;
    int o_flags = 0;
    int fd;
    /*o_flags = O_NONBLOCK;*/
    memcpy(dev_name, lnx_can_dev_prefix, prefix_len);
    memcpy(dev_name + prefix_len, board->busname, name_len);
    dev_name[prefix_len + name_len] = 0;
    printf("dev_name %s\n", dev_name);
    fd = open(dev_name, O_RDWR | o_flags);
    if (fd < 0)
    {
        fprintf(stderr, "!!! Board %s is unknown. See can_lincan.c\n", board->busname);
        goto error_ret;
    }
    printf("fd = %d\n", fd);
    // set baudrate
    params.baudrate = TranslateBaudeRate(board->baudrate);
    if (params.baudrate == 0)
    {
        goto error_ret;
    }
    params.flags = -1;  // use driver defaults
    params.sjw = -1;    // use driver defaults
    params.sample_pt = -1;  // use driver defaults
    if (ioctl(fd, CONF_BAUDPARAMS, &params) < 0)
    {
        fprintf(stderr, "canOpen_driver (lincan): IOCTL set speed failed\n");
        goto error_ret;
    }
    return (CAN_HANDLE)fd;
error_ret:
    return NULL;
}

/***************************************************************************/
int canClose_driver(CAN_HANDLE fd0)
{
    if (!fd0)
    {
        return 0;
    }
    close(fd0);
    return 0;
}
